Noisy Transformer

[DarrenSL]

I've just fitted a low voltage ventilation fan (Expelair LVDX200T) in my bathroom but am not happy at all with the constant humming noise the transformer is making. Has anyone else fitted this particular make and noticed the same?

I fitted the transformer in the loft space, screwed into a ceiling joist. The noise is loud enough to be heard all over the upstairs of the house which is particularly annoying when trying to sleep.

Have I got a duff transformer? or is there anything I could do to reduce the noise? (firstly, I'm planning to mount the transformer on the wall which should help a little).

 

[bathjobby]

Not familiar with this particular model but; all transformers vibrate slightly but if the coil assembly is secured properly you shouldn't notice it. So sounds like you have a duff one here. Are you able to check that none of the fittings, securing screws etc are loose ? If not, take it back under warranty.

 

[big-all]

the fact its firmly screwed to the joist wont help a couple of rubber washers between wood an transformer and another one under the screwhead should help

 

[RF Lighting]

Is it humming all the time or just while the fan is runnung?

 

[DarrenSL]

It hums all the time as the fan has a permanent live and a switched live.

Is not particularly loud just constant and annoying. I think the ceiling may be amplifying the noise somewhat seeing as the transformer is connected to the joist. I like the idea of using rubber washers so will give that a try (and/or fix to the wall).

Thanks.

 

[simon_d]

if the stansformer is loose, it can vibrate making the noise. have a large transformer in a UPS which vibrates, so not has some bluetack on the outside bottom of the case...

 

[securespark]

If you have an elderly HOH neighbour, and live in a terrace, relocate it to his loft.....

 

[RF Lighting]

It hums all the time as the fan has a permanent live and a switched live.

This shouldn't cause it to hum all the time. The transformer should only get power when the fan is running. (the light is on or it is over-running)

 

[DarrenSL]

I've wired it like this ...

I'm pretty sure this is right but if you disagree let me know.


Anyway, an update on the problem itself. I removed the transformer and left it freestanding on a block of polystyrene and am amazed! The result is total silence (I was at best hoping for a reduction in the noise!)
I'm planning on leaving it like this unless someone tells me its dangerous!?

 

[RF Lighting]

All the low voltage fans I have ever fitted have been wired like this:

The transformer module has a built in timer circuit so the transformer is only powered up when the fan is running, rather than how yours is (I assume it is ike a standard mains timer fan with the timer built into the fan).

Anyway, an update on the problem itself. I removed the transformer and left it freestanding on a block of polystyrene and am amazed! The result is total silence (I was at best hoping for a reduction in the noise!)
I'm planning on leaving it like this unless someone tells me its dangerous!?

The only problem with this is transformers can get quite hot (especially when they are on constantly) and there may be a risk of the polystyrene catching fire. Is there a fire proof alternative you could use such as a piece of rockwool?

 

[DarrenSL]

Thanks RF. Sounds sensible to me to have the timer in the transformer rather than the fan itself. No doubt I'll be needing a new transformer at some point in the future when mine burns out! I only bought this particular fan because I liked the facia (about £30 more than the alternative too!)

I'll take your advice and look for a fireproof alternative. Makes sense.

THanks.